Safety of Patients with Renal Artery Aneurysm to Proceed with Living Donation.

BACKGROUND: Renal artery aneurysm (RAA) is a rare condition that involves dilation of all layers of the arterial wall of the renal artery. The risk of rupture is rare, but intervention is recommended for larger aneurysms. Surgical decision-making regarding live donor renal transplantation (LDRT) centers around safety for the living donor, and laterality of the donated kidney is based on providing the donor with the best longevity pertaining to the remaining kidney. We looked to review our long-term outcomes surrounding live donor transplants from donors with RAA with ex vivo resection and reconstruction prior to implantation. METHODS: A retrospective review was done of all laparoscopic live donor transplant nephrectomies with ex vivo aneurysm resection, reconstruction, and implantation at a single center. RESULTS: Three pairs of patients underwent successful laparoscopic donor nephrectomy, RAA resection, reconstruction, and transplantation of kidney. 2 males and 1 female ages 47 to 58 years of age underwent transplantation. The donors at 5 years of follow-up were noted to be functioning appropriately with no long-term sequelae of their donation and a mean remanent kidney function of 63 mL/min. DISCUSSION: For potential live donors with asymptomatic, unilateral renal artery aneurysm and no systemic disease, live donation with ex vivo resection and reconstruction can be performed with excellent long-term donor and recipient outcomes.

Multiple infusions of ex vivo-expanded regulatory T cells promote CD163+ myeloid cells and kidney allograft survival in non-lymphodepleted non-human primates.

Clinical verification of adoptively transferred regulatory T cell (Treg) efficacy in transplantation remains challenging. Here, we examined the influence of autologous ex vivo-expanded polyclonal Tregs on kidney graft survival in a clinically relevant non-human primate model. Peripheral blood Tregs were isolated and expanded using artificial antigen presenting cells. Immunosuppression was comprised of tapered tacrolimus and CTLA4 immunoglobulin, in five animals each without or with Treg infusions. Escalating Treg doses were administered 6, 10, 13, 16, 20, 23, 27 and 30 days after transplant. Infused Tregs were monitored for Treg signature, anti-apoptotic (Bcl-2) and proliferation (Ki67) marker expression. Treg infusions prolonged median graft survival time significantly from 35 to 70 days. Treg marker (Ki67 and Bcl-2) expression by infused Tregs diminished after their infusion but remained comparable to that of circulating native Tregs. No major changes in circulating donor-reactive T cell responses or total Treg percentages, or in graft-infiltrating T cell subsets were observed with Treg infusion. However, Treg infusion was associated with significant increases in CD163 expression by circulating HLA-DR+ myeloid cells and elevated levels of circulating soluble CD163. Further, graft-infiltrating CD163+ cells were increased with Treg infusion. Thus, multiple Treg infusions were associated with M2-like myeloid cell enhancement that may mediate immunomodulatory, anti-inflammatory and graft reparative effects.

Nutritional Risks in Patients Undergoing Total Pancreatectomy Islet AutoTransplantation in the POST Consortium.

BACKGROUND AND AIMS: Total pancreatectomy with islet autotransplantation (TPIAT) can relieve pain for individuals with acute recurrent or chronic pancreatitis. However, TPIAT may increase the risk of poor nutritional status with complete exocrine pancreatic insufficiency, partial duodenectomy, and intestinal reconstruction. Our study's objective was to evaluate nutritional status, anthropometrics, and vitamin levels before and after TPIAT. METHODS: The multicenter Prospective Observational Study of TPIAT (POST) collects measures including vitamins A, D, and E levels, pancreatic enzyme dose, and multivitamin (MVI) administration before and 1-year after TPIAT. Using these data, we studied nutritional and vitamin status before and after TPIAT. RESULTS: 348 TPIAT recipients were included (68% adult, 37% male, 93% Caucasian). In paired analyses at 1-year follow-up, vitamin A was low in 23% (vs 9% pre-TPIAT, p < 0.001); vitamin E was low in 11% (vs 5% pre-TPIAT, p = 0.066), and 19% had vitamin D deficiency (vs 12% pre-TPIAT, p = 0.035). Taking a fat-soluble multivitamin (pancreatic MVI) was associated with lower risk for vitamin D deficiency (p = 0.002). Adults were less likely to be on a pancreatic MVI at follow-up (34% vs 66% respectively, p < 0.001). Enzyme dosing was adequate. More adults versus children were overweight or underweight pre- and post-TPIAT. Underweight status was associated with vitamin A (p = 0.014) and E (p = 0.02) deficiency at follow-up. CONCLUSIONS: Prevalence of fat-soluble vitamin deficiencies increased after TPIAT, especially if underweight. We strongly advocate that all TPIAT recipients have close post-operative nutritional monitoring, including vitamin levels. Pancreatic MVIs should be given to minimize risk of developing deficiencies.

Reversal of Roux-en-Y Gastric Bypass for Successful Salvage of Renal Allograft.

Enteric hyperoxaluria (EH) is a known complication of Roux-en-Y gastric bypass (RYGB) and can lead to nephrolithiasis, oxalate-induced nephropathy, and end-stage renal disease. Recurrent EH-induced renal impairment has been reported after kidney transplantation and may lead to allograft loss. EH occurs in up to one quarter of patients following malabsorption-based bariatric operations. We present a report of medically refractory EH in a renal transplant recipient with allograft dysfunction that was successfully managed with reversal of RYGB. The patient developed renal failure 7 years following gastric bypass requiring renal transplant. Following an uneventful living donor kidney transplant, the patient developed recurrent subacute allograft dysfunction. A diagnosis of oxalate nephropathy was made based on biopsy findings of renal tubular calcium oxalate deposition in conjunction with elevated serum oxalate levels and elevated 24-hr urinary oxalate excretion. Progressive renal failure ensued despite medical management. The patient underwent reversal of her RYGB, which resulted in recovery of allograft function. This report highlights an under-recognized, potentially treatable cause of renal allograft failure in patients with underlying gastrointestinal pathology or history of bariatric surgery and proposes a strategy for management of patients with persistent hyperoxaluria based on a review of the literature.

The living donor evaluation as a life-saving event.

BACKGROUND: As a population, living kidney donors have a longer life expectancy than the general population. This is generally thought to be an artifact of selection, as only healthy individuals are allowed to donate, and the operative mortality and risk of subsequent renal failure are very low. However, there may also be an additional benefit to the process, as the donor evaluation may uncover an early occult cancer or a potentially serious medical problem. While these problems may preclude donation, they may be lifesaving, as they are likely to be diagnosed and treated before the donor develops symptoms. PATIENTS AND METHODS: We looked at the incidence of occult cancer and other previously undiagnosed medical problems including renal disease, diabetes, hypertension, cardiac disease, and hepatitis C, in individuals volunteering to become a kidney donor at our center who proceeded with the evaluation between January 1, 1996 and May 31, 2011. RESULTS: Of 4088 potential donors, 19 (.46%) were discovered to have an unsuspected cancer, and 286 (7%) were found to have a previously undiagnosed medical problem. CONCLUSIONS: The living donor evaluation may lead to the early diagnosis of a life-threatening illness. This should be considered as one of the potential benefits of living donation.

Surgical approach and short-term outcomes in adults and children undergoing total pancreatectomy with islet autotransplantation: A report from the Prospective Observational Study of TPIAT.

BACKGROUND: Total pancreatectomy with islet autotransplantation (TPIAT) is a viable option for treating debilitating recurrent acute pancreatitis (RAP) and chronic pancreatitis (CP) in adults and children. No data is currently available regarding variation in approach to operation. METHODS: We evaluated surgical techniques, islet isolation and infusion approaches, and outcomes and complications, comparing children (n = 84) with adults (n = 195) enrolled between January 2017 and April 2020 by 11 centers in the United States in the Prospective Observational Study of TPIAT (POST), which was launched in 2017 to collect standard history and outcomes data from patients undergoing TPIAT for RAP or CP. RESULTS: Children more commonly underwent splenectomy (100% versus 91%, p = 0.002), pylorus preservation (93% versus 67%; p < 0.0001), Roux-en-Y duodenojejunostomy reconstruction (92% versus 35%; p < 0.0001), and enteral feeding tube placement (93% versus 63%; p < 0.0001). Median islet equivalents/kg transplanted was higher in children (4577; IQR 2816-6517) than adults (2909; IQR 1555-4479; p < 0.0001), with COBE purification less common in children (4% versus 15%; p = 0.0068). Median length of hospital stay was higher in children (15 days; IQR 14-22 versus 11 days; IQR 8-14; p < 0.0001), but 30-day readmissions were lower in children (13% versus 26%, p = 0.018). Rate of portal vein thrombosis was significantly lower in children than in adults (2% versus 10%, p = 0.028). There were no mortalities in the first 90 days post-TPIAT. CONCLUSIONS: Pancreatectomy techniques differ between children and adults, with islet yields higher in children. The rates of portal vein thrombosis and early readmission are lower in children.

Psychosocial outcomes 1-year post total pancreatectomy and autologous islet cell transplant.

BACKGROUND: A paucity of research regarding the psychosocial outcomes after TPIAT exists. METHODS: Adults (>18 years), adolescents (13-18 years), and children (5-12 years) with their parents were administered questionnaires at the time of evaluation for TPIAT and 1-year postsurgery to assess psychosocial outcomes. RESULTS: A total of 13 adults (6 male, 46%; mean age 35.2 years) and 9 children/adolescents (4 female, 44.4%; mean age 11.78 years) with CP were included in the study. A total of 69.2% of the adults and 66.7% of the children and adolescents were insulin dependent at 1-year postsurgery. In adults, improvements on the SF-36 pain (p = .001) and general health (p = .045) subscales were generally observed 1-year postsurgery. Adult patients who underwent robotic-assisted surgery compared to open surgery specifically reported better general health on the SF-36 (p < .05) at 1 year. For children and adolescents, reductions in average pain in the last week (p < .05), pain interference (p < .001), and fatigue were observed (p < .05) at 1-year postsurgery. For the entire sample, using repeated measures ANOVA and covarying for age, significant differences were found 1-year postsurgery in average pain in the last week (p = .034) and pain interference with the following categories: general activity (p < .001), walking (p = .04), normal work (p = .003), sleep (p = .002), and enjoyment in life (p = .007). CONCLUSIONS: While few transplant centers offer this treatment, the improvement in quality of life suggests this may be a viable treatment option for those with CP complicated by intractable pain. (IRB Approval PRO 19080302).

Single-cell analyses of human pancreas: characteristics of two populations of acinar cells in chronic pancreatitis.

Chronic pancreatitis (CP) is a complex inflammatory disorder with numerous associated genetic and environmental risk factors. The most distressing characteristic of CP is recalcitrant pain, often requiring surgical resection including total pancreatectomy with islet autotransplantation (TPIAT). We studied five consented subjects undergoing pancreatic resection and processed isolated cells for single-cell RNA sequencing (scRNA-Seq). Using high-dimensional transcriptomic cluster analysis, we identified 11 unique cell clusters in the pancreas tissue. These cell clusters include a cluster of undifferentiated/dedifferentiated cells and two unique clusters of acinar cells, one of which appears to be in a transitional stage. To determine the cellular response to protease inhibitor and stimulation, we treated aliquots of cells from one subject with a protease inhibitor cocktail with and without bethanechol (a muscarinic receptor agonist) at 100 and 400 µM and compared gene expression profiles. The protease inhibitors appeared to reduce cell stress. Pancreatic digestive enzymes and islet hormones were upregulated in both doses of bethanechol-treated cells compared with naïve cells. High-dose bethanechol appeared to be toxic and consistent with hyperstimulation. These studies demonstrate the feasibility of investigating human acinar cell physiology at the single-cell level and initial evidence that these cells retain responsiveness to agonist stimulation with predicted second messenger and transcriptomic responses.NEW & NOTEWORTHY We conducted single cell RNA sequencing on pancreas tissue from five individuals. We identified eleven unique cell clusters including a large population of dedifferentiated cells as well as two unique clusters of acinar cells, one of which appears to exist in a transitional state. We also examined the cellular response of pancreas tissue to stimulation and identified affected genes and pathways, including pancreatic digestive enzymes.

The Association of Smoking and Alcohol Abuse on Anxiety and Depression in Patients With Recurrent Acute or Chronic Pancreatitis Undergoing Total Pancreatectomy and Islet Autotransplantation: A Report From the Prospective Observational Study of TPIAT Cohort.

OBJECTIVES: Smoking and alcohol use are risk factors for acute and chronic pancreatitis, and their role on anxiety, depression, and opioid use in patients who undergo total pancreatectomy and islet autotransplantation (TPIAT) is unknown. METHODS: We included adults enrolled in the Prospective Observational Study of TPIAT (POST). Measured variables included smoking (never, former, current) and alcohol abuse or dependency history (yes vs no). Using univariable and multivariable analyses, we investigated the association of smoking and alcohol dependency history with anxiety and depression, opioid use, and postsurgical outcomes. RESULTS: Of 195 adults studied, 25 were current smokers and 77 former smokers, whereas 18 had a history of alcohol dependency (of whom 10 were current smokers). A diagnosis of anxiety was associated with current smoking (P = 0.005), and depression was associated with history of alcohol abuse/dependency (P = 0.0001). However, active symptoms of anxiety and depression at the time of TPIAT were not associated with smoking or alcohol status. Opioid use in the past 14 days was associated with being a former smoker (P = 0.005). CONCLUSIONS: Active smoking and alcohol abuse history were associated with a diagnosis of anxiety and depression, respectively; however, at the time of TPIAT, symptom scores suggested that they were being addressed.

Outcomes and factors leading to graft failure in kidney transplants from deceased donors with acute kidney injury-A retrospective cohort study.

Due to shortage of donor, kidney transplants (KTs) from donors with acute kidney injury (AKI) are expanding. Although previous studies comparing clinical outcomes between AKI and non-AKI donors in KTs have shown comparable results, data on high-volume analysis of KTs outcomes with AKI donors are limited. This study aimed to analyze the selection trends of AKI donors and investigate the impact of AKI on graft failure using the United states cohort data. We analyzed a total 52,757 KTs collected in the Scientific Registry of Transplant Recipient (SRTR) from 2010 to 2015. The sample included 4,962 (9.4%) cases of KTs with AKI donors (creatinine ≥ 2 mg/dL). Clinical characteristics of AKI and non-AKI donors were analyzed and outcomes of both groups were compared. We also analyzed risk factors for graft failure in AKI donor KTs. Although the incidence of delayed graft function was higher in recipients of AKI donors compared to non-AKI donors, graft and patient survival were not significantly different between the two groups. We found donor hypertension, cold ischemic time, the proportion of African American donors, and high KDPI were risk factors for graft failure in AKI donor KTs. KTs from deceased donor with AKI showed comparable outcomes. Thus, donors with AKI need to be considered more actively to expand donor pool. Caution is still needed when donors have additional risk factors of graft failure.

Arguments against the Requirement of a Biological License Application for Human Pancreatic Islets: The Position Statement of the Islets for US Collaborative Presented during the FDA Advisory Committee Meeting.

The Food and Drug Administration (FDA) has been regulating human islets for allotransplantation as a biologic drug in the US. Consequently, the requirement of a biological license application (BLA) approval before clinical use of islet transplantation as a standard of care procedure has stalled the development of the field for the last 20 years. Herein, we provide our commentary to the multiple FDA's position papers and guidance for industry arguing that BLA requirement has been inappropriately applied to allogeneic islets, which was delivered to the FDA Cellular, Tissue and Gene Therapies Advisory Committee on 15 April 2021. We provided evidence that BLA requirement and drug related regulations are inadequate in reassuring islet product quality and potency as well as patient safety and clinical outcomes. As leaders in the field of transplantation and endocrinology under the "Islets for US Collaborative" designation, we examined the current regulatory status of islet transplantation in the US and identified several anticipated negative consequences of the BLA approval. In our commentary we also offer an alternative pathway for islet transplantation under the regulatory framework for organ transplantation, which would address deficiencies of in current system.

Donation after circulatory death is associated with increased fibrosis on 1-year post-transplant kidney allograft surveillance biopsy.

AIM: The use of kidneys donated after circulatory death (DCD) provides an invaluable expansion of the organ supply for transplantation. Here, we investigated the effect of DCD on fibrotic changes on 1 1-year post 1-transplant surveillance kidney allograft biopsy. METHODS: Recipients of a deceased donor kidney transplant between 2013 and 2017 at a single institution, who survived 1 year and underwent surveillance biopsy, were included in the analysis (n = 333: 87 DCD kidneys, 246 kidneys donated after brain death [DBD]). Banff scores for interstitial fibrosis and tubular atrophy were summed as IFTA and compared between the groups. RESULTS: DCD and DBD groups were comparable for baseline characteristics. Delayed graft function was 39% in DCD versus 19% in DBD, P = .0002. Patient and graft survival were comparable for DCD and DBD cohorts. IFTA scores were higher in DCD compared to DBD (2.43±..13 vs. 2.01±..08, P = .0054). On multivariate analysis, the odds of IFTA > 2 in the DCD group was 2.5× higher (95%CI: 1.354.63) than in the DBD group. Within the DCD group, kidneys with IFTA > 2 had inferior 5-year graft survival (P = .037). CONCLUSION: Compared to DBD kidneys, DCD kidneys developed a greater degree of fibrotic changes on 1-year post-transplant surveillance biopsy, which affected graft longevity within the DCD cohort.

Targeting CXCR1/2 in the first multicenter, double-blinded, randomized trial in autologous islet transplant recipients.

Several cytokines and chemokines are elevated after islet infusion in patients undergoing total pancreatectomy with islet autotransplantation (TPIAT), including CXCL8 (also known as interleukin-8), leading to islet loss. We investigated whether use of reparixin for blockade of the CXCL8 pathway would improve islet engraftment and insulin independence after TPIAT. Adults without diabetes scheduled for TPIAT at nine academic centers were randomized to a continuous infusion of reparixin or placebo (double-blinded) for 7 days in the peri-transplant period. Efficacy measures included insulin independence (primary), insulin dose, hemoglobin A1c (HbA1c ), and mixed meal tolerance testing. The intent-to-treat population included 102 participants (age 39.5 ± 12.2 years, 69% female), n = 50 reparixin-treated, n = 52 placebo-treated. The proportion insulin-independent at Day 365 was similar in reparixin and placebo: 20% vs. 21% (p = .542). Twenty-seven of 42 (64.3%) in the reparixin group and 28/45 (62.2%) in the placebo group maintained HbA1c ≤6.5% (p = .842, Day 365). Area under the curve C-peptide from mixed meal testing was similar between groups, as were adverse events. In conclusion, reparixin infusion did not improve diabetes outcomes. CXCL8 inhibition alone may be insufficient to prevent islet damage from innate inflammation in islet autotransplantation. This first multicenter clinical trial in TPIAT highlights the potential for future multicenter collaborations.

Circulating miRNA in Patients Undergoing Total Pancreatectomy and Islet Autotransplantation.

Circulating microRNAs (miRNAs) can be biomarkers for diagnosis and progression of several pathophysiological conditions. In a cohort undergoing total pancreatectomy with islet autotransplantation (TPIAT) from the multicenter Prospective Observational Study of TPIAT (POST), we investigated associations between a panel of circulating miRNAs (hsa-miR-375, hsa-miR-29b-3p, hsa-miR-148a-3p, hsa-miR-216a-5p, hsa-miR-320d, hsa-miR-200c, hsa-miR-125b, hsa-miR-7-5p, hsa-miR-221-3p, hsa-miR-122-5p) and patient, disease and islet-isolation characteristics. Plasma samples (n = 139) were collected before TPIAT and miRNA levels were measured by RTPCR. Disease duration, prior surgery, and pre-surgical diabetes were not associated with circulating miRNAs. Levels of hsa-miR-29b-3p (P = 0.03), hsa-miR-148a-3p (P = 0.04) and hsa-miR-221-3p (P = 0.01) were lower in those with genetic risk factors. Levels of hsa-miR-148a-3p (P = 0.04) and hsa-miR-7-5p (P = 0.04) were elevated in toxic/metabolic disease. Participants with exocrine insufficiency had lower hsa-miR-29b-3p, hsa-miR-148a-3p, hsa-miR-320d, hsa-miR-221-3p (P < 0.01) and hsa-miR-375, hsa-miR-200c-3p, and hsa-miR-125b-5p (P < 0.05). Four miRNAs were associated with fasting C-peptide before TPIAT (hsa-miR-29b-3p, r = 0.18; hsa-miR-148a-3p, r = 0.21; hsa-miR-320d, r = 0.19; and hsa-miR-221-3p, r = 0.21; all P < 0.05), while hsa-miR-29b-3p was inversely associated with post-isolation islet equivalents/kg and islet number/kg (r = -0.20, P = 0.02). Also, hsa-miR-200c (r = 0.18, P = 0.03) and hsa-miR-221-3p (r = 0.19, P = 0.03) were associated with islet graft tissue volume. Further investigation is needed to determine the predictive potential of these miRNAs for assessing islet autotransplant outcomes.

Preoperative ERCP has no impact on islet yield following total pancreatectomy and islet autotransplantation (TPIAT): Results from the Prospective Observational Study of TPIAT (POST) cohort.

BACKGROUND AND AIMS: Many patients undergoing total pancreatectomy with islet autotransplant (TPIAT) for severe, refractory chronic pancreatitis or recurrent acute pancreatitis have a history of endoscopic retrograde cholangiopancreatography (ERCP). Using data from the multicenter POST (Prospective Observational Study of TPIAT) cohort, we aimed to determine clinical characteristics associated with ERCP and the effect of ERCP on islet yield. METHODS: Using data from 230 participants (11 centers), demographics, pancreatitis history, and imaging features were tested for association with ERCP procedures. Logistic and linear regression were used to assess association of islet yield measures with having any pre-operative ERCPs and with the number of ERCPs, adjusting for confounders. RESULTS: 175 (76%) underwent ERCPs [median number of ERCPs (IQR) 2 (1-4). ERCP was more common in those with obstructed pancreatic duct (p = 0.0009), pancreas divisum (p = 0.0009), prior pancreatic surgery (p = 0.005), and longer disease duration (p = 0.004). A greater number of ERCPs was associated with disease duration (p < 0.0001), obstructed pancreatic duct (p = 0.006), and prior pancreatic surgery (p = 0.006) and increased risk for positive islet culture (p < 0.0001). Mean total IEQ/kg with vs. without prior ERCP were 4145 (95% CI 3621-4669) vs. 3476 (95% CI 2521-4431) respectively (p = 0.23). Adjusting for confounders, islet yield was not significantly associated with prior ERCP, number of ERCPs, biliary or pancreatic sphincterotomy or stent placement. CONCLUSIONS: ERCP did not appear to adversely impact islet yield. When indicated, ERCP need not be withheld to optimize islet yield but the risk-benefit ratio of ERCP should be considered given its potential harms, including risk for excessive delay in TPIAT.

The histopathology of SPINK1-associated chronic pancreatitis.

BACKGROUND: The identification of genetic risk factors for chronic pancreatitis, such as PRSS1, CFTR and SPINK1, provides the opportunity to define key pathologic hallmarks and etiologic-specific changes. For example, pancreata from PRSS1 and CFTR patients exhibit progressive lipomatous atrophy without significant fibrosis. Considering the pathology of SPINK1-associated pancreatitis is ill-defined, we examined the pancreata of SPINK1 patients with chronic pancreatitis. METHODS: Histologic sections after total pancreatectomy with islet autotransplantation and associated clinicopathologic data were collected from 28 patients with SPINK1 germline alterations. Clinical findings, germline data, anatomic anomalies and pathologic findings were descriptively evaluated. RESULTS: Patients ranged in age from 5 to 48 years (median, 21.6 years) with abdominal pain between 2 and 25 years (median, 5.8 years). Most patients were SPINK1 heterozygous and 14 (50%) had co-occurring CFTR (n = 12) and CTRC (n = 2) mutations. Other pancreatitis risk factors included anatomic anomalies (n = 9) and tobacco use (n = 1). Overall, 24 (86%) patients had additional pancreatitis-associated germline alterations, SPINK1 homozygosity, anatomic anomalies or environmental factors. Examination of pancreata revealed a sequential pattern of exocrine parenchymal loss and replacement by prominent fibrosis, dependent on the duration of abdominal pain. No malignancies were identified, but low-grade pancreatic intraepithelial neoplasia was present for 2 cases. CONCLUSIONS: Within this descriptive study, SPINK1-associated pancreatitis is characterized by parenchymal fibrosis and suggests divergent pathophysiologic mechanisms from PRSS1 and CFTR-associated pancreatitis. Moreover, SPINK1 patients frequently had additional etiologic factors that did not impact the development of pancreatic fibrosis and may implicate SPINK1 as a disease modifier gene.

Donor acute kidney injury and its effect on 1-year post-transplant kidney allograft fibrosis.

Transplantation of kidneys from deceased donors with acute kidney injury (AKI) can expand the donor pool. We investigated the effect of donor AKI on renal function and chronic changes on protocol biopsies at 1-year post-transplant. Donor AKI was defined according to Acute Kidney Injury Network (AKIN) criteria. Between 2013 and 2017, 333 kidneys were transplanted and subsequently biopsied after 1 year. Fifty-three kidneys from AKI donors (AKIN stage I n = 42, stage II n = 8, stage III n = 3) were compared to 280 kidneys from non-AKI donors. At 1-year follow-up, patient and graft survival were comparable. Donor AKI was not predictive of IFTA (Banff interstitial fibrosis plus tubular atrophy scores) at 1-year post-transplant biopsy (2.10 ± 1.28 in AKI, 2.09 ± 1.22 in non-AKI, P = .95). Donor AKI was also not associated with progression of IFTA from 3 to 12 months (P = .69), or inferior glomerular filtration rate (eGFR, P = .94). In a multivariate analysis, the odds of IFTA >2 were comparable between AKI and non-AKI groups. In conclusion, the transplantation of kidneys from donors with predominantly stage I AKI results in comparable function and degree of fibrosis on protocol biopsies 1-year post-transplant. Selected grafts from donors with AKI are a valuable tool for expanding the donor pool for kidney transplantation.

A Study on the Effect of Patient Characteristics, Geographical Utilization, and Patient Outcomes for Total Pancreatectomy Alone and Total Pancreatectomy With Islet Autotransplantation in Patients With Pancreatitis in the United States.

OBJECTIVES: A selective therapy for pancreatitis is total pancreatectomy and islet autotransplantation. Outcomes and geographical variability of patients who had total pancreatectomy (TP) alone or total pancreatectomy with islet autotransplantation (TPIAT) were assessed. METHODS: Data were obtained from the Healthcare Cost and Utilization Project National Inpatient Sample database. Weighed univariate and multivariate analyses were performed to determine the effect of measured variables on outcomes. RESULTS: Between 2002 and 2013, there were 1006 TP and 825 TPIAT in patients with a diagnosis of chronic pancreatitis, and 1705 TP and 830 TPIAT for any diagnosis of pancreatitis. The majority of the TP and TPIAT were performed in larger urban hospitals. Costs were similar for TP and TPIAT for chronic pancreatitis but were lower for TPIAT compared with TP for any type of pancreatitis. The trend for TP and TPIAT was significant in all geographical areas during the study period. CONCLUSIONS: There is an increasing trend of both TP and TPIAT. Certain groups are more likely to be offered TPIAT compared with TP alone. More data are needed to understand disparities and barriers to TPIAT, and long-term outcomes of TPIAT such as pain control and glucose intolerance need further study.

Preliminary assessment of the feasibility of autologous myeloid-derived suppressor cell infusion in non-human primate kidney transplantation.

Myeloid-derived suppressor cells (MDSC) are a heterogenous population of immunosuppressive myeloid cells now considered important immune regulatory cells in diverse clinical conditions, including cancer, chronic inflammatory disorders and transplantation. In rodents, MDSC administration can inhibit graft-versus-host disease lethality and enhance organ or pancreatic islet allograft survival. There is also evidence, however, that under systemic inflammatory conditions, adoptively-transferred MDSC can rapidly lose their suppressive function. To our knowledge, there are no reports of autologous MDSC administration to either human or clinically-relevant non-human primate (NHP) transplant recipients. Monocytic (m) MDSC have been shown to be more potent suppressors of T cell responses than other subsets of MDSC. Following their characterization in rhesus macaques, we have conducted a preliminary analysis of the feasibility and preliminary efficacy of purified mMDSC infusion into MHC-mismatched rhesus kidney allograft recipients. The graft recipients were treated with rapamycin and the high affinity variant of the T cell co-stimulation blocking agent cytotoxic T lymphocyte antigen 4 Ig (Belatacept) that targets the B7-CD28 pathway. Graft survival and histology were not affected by infusions of autologous, leukapheresis product-derived mMDSC on days 7 and 14 post-transplant (cumulative totals of 3.19 and 1.98 × 106 cells/kg in n = 2 recipients) compared with control monkeys that did not receive MDSC (n = 2). Sequential analyses of effector T cell populations revealed no differences between the groups. While these initial findings do not provide evidence of efficacy under the conditions adopted, further studies in NHP, designed to ascertain the appropriate mMDSC source and dose, timing and anti-inflammatory/immunosuppressive agent support are likely to prove instructive regarding the therapeutic potential of MDSC in organ transplantation.